Fuel-injection system



M arch19,192 9. Lo, FRENCH 1,705,665

\ FUEL INJECTION SYSTEM Filed Dec. 31, 1925 I 97 .Efi I1 I 95 99 E/Vl/VE Ell EN INVENTOR.

. Patented Mar. 19,1929

-' i, UNITED -sTATEs LOU IS O. FRENCH, OF,MI l'JWAUKEE, WISCONSIN.

Application filed December engine, when the engine is stopped the conply passages to the, engine cylinder are ele-i tacts of the switchmechanism may be engaged so that should the operator turn on the fuelcontrol switch previous to turnlng over the engine one of the injectorValves may be opened before the engine is started, and while the fuel isnot then under pumping pressure some of the fuel ma dribble into theengine cylinder if'parts 0 the fuel supvated. To obviate this difficultyone of the objects of this invention is to prevent the operation of theelectromagnetically-operated i alves until the engine is being startedor turned over.

In some instances it is desirable to make.

. FUEL-INJECTION sysrnim.

a1, 1925. Serial NT). 78,641.

Fig. 5 is a diagrammatic View of a fuel in ection system embodying 1 theinvention,

parts being broken away and parts being.

shown in section.

, Referring to I Fig. 5, the fuel'injection system includes 'a fuelsupply tank 6 connected by a pipe 7 with a fuel pump 8 ,o f any suitableconstruction, which is generally driven by the engine and is of a ty eto insure a relativelyconstant supply of to a pressure pipe 9 in iwhithe fuel is maintained, while the pump is operating, at substantiallyconstant pressure by means of fuel a pressure valve mechanismof anysuitable construction. As shown, pressure valve mechanism 10 includes a'casin parts 11 and 12 with a diapl ra'gm 13 secured between them, avalve 14 working in a slotted guide tube 14 and being normally urged; bya spring 15 acting on thediaphragm to close off communication betweenthe presexcess fuel to the tank'fiythe tension of the .the enginedirectly reversible, and another spring 15 being adjustableby means of aobject of this invention is to'provide a fuel injection system whereindirect reversal by preignitionmay be obtained through sw1tch mechanismassociated with the control circuit ofthe electrically-controlled fuelinjection system. A A further object of the invention is to provide, inconnection with a governor-controlled switch mechanism for fuelinjectionsystems of the type above referred to, a timing cam which at startingaccommodates for the relatively slow speed of the engine thatinayrezgist during this period, and prevents excessive charges of fuelbeing introduced into the engine cylinder during starting.

The invention further consists in the several features hereinafter setforth and. more particularly defined by claims at the conclusion hereof.Inthe drawings, Fig.1 is a vertical sectional view through controlswitch mechanism embodyingthe invention, parts being broken way;

Fig.

. 3-3 of Fig. 1;

, Fig. 4 is a detail. sectional view of switch mechanism used in thesystem;

slide-block 18 associated with a bolt 19 in threaded engagement with thepart 12 of the casing. From the pipe .9 branch pipes.

20 respectivelydead to the electromagnet made up of y .75- sure pipe 9'and the,chambe r 16 which communicates with a pipe 17 that returns theically-o'perated fuel injector valves 21 which include a control valve22 having an arma ture' 23 associated with an electromagnet 24 andcontrolling passa e of 'fuel from its supply pipe 20 through the valvecasin and the fuel nozzle 25 into the cylinder of t e engine in the head26 of which the injector valve is.

- mounted, a

spring 27 normally tending to close theva ve which is opened by theelectroma net a the desired time and for the desire period. Asan'ysuitable construction of electromagnetic valve may be used in thesystem, further description thereof is deemed unnecessary.

shown in Figs. 1 and 2, and includes a shaft 28 driven by the engine, aswitch including The switch mechanism for controlling the operation ofthe electnomagnetic valves is va fixed contact 29 and a movable contact30,; a timing cam 31 mounted onv the shaft 28 and cooperating with thecontact 30 to open and close the control circuit, and in the case of amulti-cylinder engine distributor mechanism includinga brush 31 mountedon the shaft 28 and cooperating with contacts 32 res ectively associatedwith the engine cylin ers. y r r The means for preventing the operationof the injection valves until the engine is turned section 38 of atwopart casing 39 having 41 in the pipe 9, the parts 38 and 39 being bybolts 38, plunger 37 being normally urged to open Thus, when theswltches 54 and 33 are connected together" and to a diaphragm 42 toprevent possible leakage, the

fore the engine is started and the switch mechanism 33 not used, it isapparent that if one of the electromagnets is then receiving currentthrough the distributor contact 32, with the result that its controlvalve is open, the engine cylinder. However, with the switch mechanism33 included, the control circuit to the electromagnets cannot becompleted until the engine has been turned over to such an extent thatthe pump 8, driven thereby, has established a pressure head of fuel inthe pipe '9 whichtheri acts upon the diaphragm 42 to move the plunger 37and the bridging contact 36 so as to close! the circuit through thecontacts 35 and 34.

circuit. position by a spring 44 interposed closed and t e contacts 47is in contact with between it and the section 38. Thus when the contacts45 and' 46, current W'lll flow fuel pressure builds up in the pipe 9 thediaphragm 42is flexed outwardly thereby and ence the plunger 37 is movedoutwardly,

I and thus the contact 36 is moved into ennected by a bridgin' gagementwith the contacts and 35 to.

close the control circuit.

, The switch" mechanism 44, for use in reversing the engine, includes a.pair of contacts and 46'suitably insulated from each other and supportedupon a block 44 ofainsulating material and adapted to be concontact 4Tcarried by a manually-operate plun er 48 which is normally movedto-ficlose position by a s ring 49. This switch is associated with t econtrol switch. mechanism so that it operable simultaneously with theshifting o the contacti30 angularly, relative-to the cam and is hereshown as mounted on the lever 50 secured .to the angularlyadjustablecasing 51 of the control switch, though it will be understoodthat it may be associated with linkage for operating said lever 50 ,Ifrom a distant point.

The circuit connections for the various units of the system are shown inFig. 5, wherein the numeral 5% designates a battery and-53 a conductorconnecting one side i of the battery with the contact 35 and includingamanual cut-out switch 54. A conductor 55- connects the contact 34 withthe,

. contact 45'and a conductor 56 connects the X 7 connection 59.

contact .46 with the fixed contact 29. The

. contact 30 is grounded at 57 "and a condenser.

58 is connected across the-contacts 29 and 30 to reduce arcing. Oneterminal of thecoil of each eleotromagnet has a round The other side oftile battery 52is connected by a conductor 60 to the brush 31 and eachof the contacts 32 isconnctd to the other terminal of the etil of each,electromagne't by a conductor 61* whlch may include a resistance 62 toreduce the time constantof the -magnet circuit.

If the switch 54 is closed by the operator and the contact 30 is inclosed position befrom one side of the battery 52 through conductor 53,contacts 35, 36 and 34, conductor 55, contacts 45, 47 and 46, conductor56, contacts 29 and 30 (assuming the cam 31 has permitted thecontact 30to move to closed position) to ground 57. At this time is passes throughthe nozzle 25 into the cylinder of the engine at the desired time and byreason of the cam 31, hereinafter described, in the desired amount. Thenas-the engine continues, to rotate the contact-30 will again move intocircuit-closing relation with the contact 29 when the brush 31 has movedinto engagement with the other distributor contact so that the othercylinder of the engine will receive its fuel charge at the proper timein the cycle.

In case it is desired to reverse theengine, shifting the lever 5% andthereby rotatin the case 51- will cause the contacts 30 an 29 to bemoved angularly relative tothe cam 31 andthis will necessarily changethe cyclic timing of the "charge. Thus, for a two cycle engine of theport scavenging type, if we assume that the fuel is being injected nearthe, end of the compression stroke and the engine is running in onedirection, throwing out the engine clutch and pressing on the plunger'48 to separate the contact 47 from the contacts 45 and 46 cuts oil thesupply of fuel and allowsthe engine to slowdown. When'the engine hasslowed down sufiicie'ntly the lever 50, with the switch 44 still heldopen, is turned so as to advance the time of closing of the contacts 30and 29 to the beginning of the compression stroke and the switch 44 isthen allowed to close so that the control circuit is rendered operativeto inject a charge of fuel at the beginning of the compression stroke,with the result that before the'piston completes its compression strokea preignition will occurvvhich will drive the piston down-' wardly andthus turn the engine over in the opposite direction. As soon as thisreversaltakes place the operator opens switch 44: and moves the leverback to a running position which will again cause the fuel to bedelivered near the end of the compres sion stroke with the enginernnning regularly in the reverse direction. Thus, by providing theswitch 44 f r operation in conjunction with the means for changing thetiming of the control switch the fuel injection period may be changed toreversethe direction of the engine. In the case of a four cycle engineitwill, of course, be understood that the timing of the inlet andexhaust valves for eflecting a reversal by well-known mechanisms forthis purpose which are commonly used on Diesel type engmes would be usedin conjunctiomwitlrthe changing" of "the time of fuel injectionto effecta reversal of the engine, but as the 1 present invention is directed tothe fuel injection system alone no special form of valve-operatingmechanism for .four cycle engines has been shown. W

Referring to Figs. 1 and 2, wherein a control switch mechanism is shownin detail,

the numeral 63 designates a two-part. casing, and-51 a switch casingmounted on the casing 63 for angular adjustment frelativethereto, as bymeans of screws 64 in casing 51, having pm projections extending into anannular groove 65 in the casing 63, and 66 a cover secured to saidswitchcasing by clips 67.

- The shaft 28 has a tight fit in the inner race of the ball-bearin 68,with a shoulder 69 adjacent said ring,a d the otherrace ring is fittedto the casing 63, whereby the shaft is journalled in the casing andprevented from moving upwardly. Y

rotate with the shaft 28 by screws 74 andhas a bore 75 in which thesleeve 72 is, free to move within the limits determined by a lonvgitudinal slot 76 in said sleeve, and a pin 77 on the ,hub of the spider73. The sleeve movement'is effected by any suitable governorassociatedwith the spider-'7 3. As shown keyway 'formed 7 the oppositelydisposed arms of the spider have, levers 78 pivotally mounted thereon,

their forked ends 79 being provided with pins 80, mounted in an annulargroove 81 formed in the upper part ofthe sleeve,

their outer ends carrying the weights 82. A spring 83, acting inopposition to the govepnor weights, is interposed between the upper endof the sleeve 72 and a manually-con- .trolledcollar 84 slidably mountedon the shaft 28. The collar is moved manually by alever 85' pivotallymounted on the casing and having forked ends 86, provided with pinprojections engaging in the groove of said collar, and an e'xteriorlydisposed operating arm.

- A ball-bearing .87 is located between the hub of the spider andthecasing' 63.

The cam 31 has one or more, the number dependingupon the number ofengine cylinders, tapered reliefs 88 formed thereincwithone side, theadvancing side, preferably parallel withQthe axis of the cam so thatforany given angular adjustment of the casing 51 the circuit closing'period will begin at the same time. The contact 30 is suitably pivotedat 89 and is normally urged against the cam by a spring 90 and basespherical projection 91 engaging said cam. ,It will be noted from thedrawings that the reliefs 88 gradually taper outwardly from the upperend 92 to an intermediate point and then taper toward a point 93 attheir lower ends.

These tapered reliefs permit the contact 30.

to remain in engagement with the contact 29 for longer or shorterrelative periods of time, depending upon the position of the cam 31, andhence the duration of current flow in the control circuit or ircuits maybe varied with the .result that the electromagnets are energized forvarying periods of time/so that the valves are held open forcorresponding periods and thus varying amounts .of fuel are delivered tothe engine cylinders in proper'cyclic sequence through the connection ofthis switch mechanism with the brush 31 and contacts 32. As

lated from, the shaftr28, and is urged'by a spring 92 againstthecommutator track 93 having the contacts 32 inset therein, and the shownthe brush 31 is mounted on, but insu- I brush receives its currentfrom'a brush 941' urged by a spring 95against the brush 31 and mountedin a member 96 provided with terminal connections 97. The contacts 32have studs98 secured thereto provided with terminal connections 99. Thecurrent to the contact 29 is led 'in through 'theterminal support 100insulated from the case 51 and .gonnected with the conductor 56. i

As the speed of the engine increases the cam 31 Will ,be moyedlongitudinally of the shaft 28 by the action of the governorweightsswinging outwardly and the sleeve 72 moving upwardly so thatdifferent por-' tions of the tapered [reliefs 88 will be brought intooperative relation with the eam As the upper end 92 of the relief of thecam is relatively short, the engine may be turned over slowly, as instarting by hand, without furnishing-excessive amounts of fuel to theengine. Furthermore, it willJoenoted, that the'cam may be designed'sothat greater quantities of fuel are furnished at intermediate speedsthan at the hi her speeds where the cam is operated .by t e governor,and this is desirable for/certain kinds of power W0rk. v t

Fro'm'the "foregoing description it will be noted'that I have providedmeans for preventing feeding of fuel to the engine cylinder until theengine is'actually being started; means for preventing an excessivecharge when the engine is turned over slowly during. starting; andnfeans permitting of the ready reversal of the engine by preignition.

I- desire it to be'understood that this invenution is not to be li''tedto any specific form orarrangement of parts except in 'so far assuch limitations are specified in the claimsornecessitated by the priorart. 7

What I claim as my invention is: 1. In a fuel injection system, thecombination of a fuel injector valve, an electromagnet controlling theoperation of said 'valve, a control ,circuit for said, electromagnet.inc uding circuit control mechanism controlled by the engine, meansforsupplying fuel to said injector, and automatically-op crating switchmeans for preventing opera? nor takes up its action.

-tion of the control ci being started. 1

2. In a fuel injection system wherein the rcuit until the engine is w a1,705,666 r livered to said valve from a pressure system including apump, the combination with such switch mechanism in said control circuitto render said circuit inoperative .until the fuelpressure builds up insaid system during the starting of the engine. 3

-3. In a .fuel 'njection system, the coinbination with a fuel-meteringdevice for controlling the supply of fuel delivered to y 60. system, offuel-pressure,-controlle"d the engine, of an electromagnet controllingthe operation of device, -a control circuit for said electromagnetincluding circuit control means and a manually-operated member for,varying the timing of said circuit control means, and switch means insaid control circuit mechanically associatedwith' said manually-operatedmember ,whereby the operator may open "said control cir-- cuit as hemoveslsaid manually-operated member to permit reversal of the engine bythe injection of a preigniting charge of fuel into the engine cylinder.

4. In a fuel injection system; circuit control mechanism fora meteringcontrol electromagnet, comprising a switch including a movable contact,an engine-driven cam for operating said cont-act, a governor, meansoperated by said governor for adjusting'th'e .came and switch 'relativeto each other to vary the duration of the circuit-closing periods ofsaid switch, said cam havinga reliefsurface controlling the closing ofthe switch contacts and preventing excessive quantities of fuel beingdelivered tothe engine during starting and before the gover-In-testimony whereof, I aflix my signa-

